Nerves and nerve lesions of the upper limb

Question 1

What is the nerve supply of the upper limb?

Answer 1

The upper limb is supplied by the brachial plexus, which includes major nerves such as the axillary, radial, musculocutaneous, ulnar, and median nerves.

Question 2

What are the spinal nerves involved in the brachial plexus?

Answer 2

C5, C6, C7, C8, and T1.

Question 3

Which nerve supplies the deltoid and teres minor muscles?

Answer 3

Axillary nerve (C5, C6).

Question 4

Which nerve is responsible for the extension of the forearm and wrist?

Answer 4

Radial nerve.

Question 5

What is the function of the musculocutaneous nerve?

Answer 5

Innervates the flexor muscles of the arm, including coracobrachialis, biceps, and brachialis.

Question 6

Which nerve supplies the flexor carpi ulnaris and the medial half of the flexor digitorum profundus?

Answer 6

Ulnar nerve.

Question 7

Which nerve innervates the majority of the muscles in the anterior compartment of the forearm?

Answer 7

Median nerve.

Question 8

What is the clinical presentation of radial nerve injury?

Answer 8

Wrist drop, paralysis of extensor muscles, and sensory loss in the dorsal aspect of the radial 3 ½ fingers.

Question 9

Fill in the blank: Loss of skin sensation and muscle power is associated with _______.

Answer 9

[nerve injury].

Question 10

What is the anatomical basis of nerve injuries?

Answer 10

The level of injury (roots, spinal nerves, plexus, peripheral nerve) determines the pattern of loss of function.

Question 11

True or False: The ulnar nerve passes behind the medial epicondyle of the humerus.

Answer 11

True.

Question 12

What is the presentation of median nerve injury at the carpal tunnel?

Answer 12

Loss of coordination and strength of the thumb, inability to oppose the thumb, and sensory loss in the lateral 3 ½ digits.

Question 13

What is the clinical presentation of ulnar nerve compression at the cubital tunnel?

Answer 13

Claw hand and sensory loss in the medial 1 ½ fingers.

Question 14

What is the role of the anterior interosseous nerve?

Answer 14

Innervates deep muscles of the anterior forearm, excluding flexor carpi ulnaris and the medial part of flexor digitorum profundus.

Question 15

List the five major limb nerves derived from the brachial plexus.

Answer 15

• Axillary nerve
• Radial nerve
• Musculocutaneous nerve
• Median nerve
• Ulnar nerve

Question 16

What are the main symptoms of carpal tunnel syndrome?

Answer 16

Ape hand presentation and sensory loss in the lateral 3 ½ fingers.

Question 17

Fill in the blank: The _______ nerve is responsible for the innervation of the thenar muscles.

Answer 17

[median nerve].

Question 18

What is the sensory innervation of the radial nerve?

Answer 18

Skin on the radial 3 & ½ fingers on the dorsal aspect of the hand.

Question 19

What is the clinical presentation of a musculocutaneous nerve injury?

Answer 19

Weakness in flexion of the shoulder and elbow joint, with sensory loss in the lateral forearm.

Question 20

True or False: The median nerve runs with the ulnar artery in the arm.

Answer 20

False.

Question 21

What is the consequence of a mid-shaft fracture of the humerus?

Answer 21

Radial nerve injury leading to wrist drop and sensory loss in the dorsal aspect of the radial 3 ½ fingers.

Question 22

What are the dermatomes of the upper limb?

Answer 22

Defined areas of skin innervated by specific spinal nerves.

Question 23

What are the additional branches of the brachial plexus?

Answer 23

• Dorsal scapular nerve
• Long thoracic nerve
• Nerve to subclavius
• Suprascapular nerve
• Pectoral nerves
• Subscapular nerves
• Thoracodorsal nerve
• Medial cutaneous nerves of arm and forearm

Question 24

What is the ‘hand of benediction’?

Answer 24

A presentation associated with proximal median nerve lesions, where the patient cannot flex the second and third fingers.

Question 25

What are the symptoms of ulnar nerve injury at the wrist?

Answer 25

Claw hand and sensory loss in the medial 1 ½ fingers.